drivers/usb/gadget/udc/bdc/bdc_core.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * bdc_core.c - BRCM BDC USB3.0 device controller core operations
   4  *
   5  * Copyright (C) 2014 Broadcom Corporation
   6  *
   7  * Author: Ashwini Pahuja
   8  */
   9 #include <linux/module.h>
  10 #include <linux/kernel.h>
  11 #include <linux/slab.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/ioport.h>
  16 #include <linux/io.h>
  17 #include <linux/list.h>
  18 #include <linux/delay.h>
  19 #include <linux/dma-mapping.h>
  20 #include <linux/dmapool.h>
  21 #include <linux/of.h>
  22 #include <linux/phy/phy.h>
  23 #include <linux/moduleparam.h>
  24 #include <linux/usb/ch9.h>
  25 #include <linux/usb/gadget.h>
  26 #include <linux/clk.h>
  27
  28 #include "bdc.h"
  29 #include "bdc_dbg.h"
  30
  31 /* Poll till controller status is not OIP */
  32 static int poll_oip(struct bdc *bdc, int usec)
  33 {
  34         u32 status;
  35         /* Poll till STS!= OIP */
  36         while (usec) {
  37                 status = bdc_readl(bdc->regs, BDC_BDCSC);
  38                 if (BDC_CSTS(status) != BDC_OIP) {
  39                         dev_dbg(bdc->dev,
  40                                 "poll_oip complete status=%d",
  41                                 BDC_CSTS(status));
  42                         return 0;
  43                 }
  44                 udelay(10);
  45                 usec -= 10;
  46         }
  47         dev_err(bdc->dev, "Err: operation timedout BDCSC: 0x%08x\n", status);
  48
  49         return -ETIMEDOUT;
  50 }
  51
  52 /* Stop the BDC controller */
  53 int bdc_stop(struct bdc *bdc)
  54 {
  55         int ret;
  56         u32 temp;
  57
  58         dev_dbg(bdc->dev, "%s ()\n\n", __func__);
  59         temp = bdc_readl(bdc->regs, BDC_BDCSC);
  60         /* Check if BDC is already halted */
  61         if (BDC_CSTS(temp) == BDC_HLT) {
  62                 dev_vdbg(bdc->dev, "BDC already halted\n");
  63                 return 0;
  64         }
  65         temp &= ~BDC_COP_MASK;
  66         temp |= BDC_COS|BDC_COP_STP;
  67         bdc_writel(bdc->regs, BDC_BDCSC, temp);
  68
  69         ret = poll_oip(bdc, BDC_COP_TIMEOUT);
  70         if (ret)
  71                 dev_err(bdc->dev, "bdc stop operation failed");
  72
  73         return ret;
  74 }
  75
  76 /* Issue a reset to BDC controller */
  77 int bdc_reset(struct bdc *bdc)
  78 {
  79         u32 temp;
  80         int ret;
  81
  82         dev_dbg(bdc->dev, "%s ()\n", __func__);
  83         /* First halt the controller */
  84         ret = bdc_stop(bdc);
  85         if (ret)
  86                 return ret;
  87
  88         temp = bdc_readl(bdc->regs, BDC_BDCSC);
  89         temp &= ~BDC_COP_MASK;
  90         temp |= BDC_COS|BDC_COP_RST;
  91         bdc_writel(bdc->regs, BDC_BDCSC, temp);
  92         ret = poll_oip(bdc, BDC_COP_TIMEOUT);
  93         if (ret)
  94                 dev_err(bdc->dev, "bdc reset operation failed");
  95
  96         return ret;
  97 }
  98
  99 /* Run the BDC controller */
 100 int bdc_run(struct bdc *bdc)
 101 {
 102         u32 temp;
 103         int ret;
 104
 105         dev_dbg(bdc->dev, "%s ()\n", __func__);
 106         temp = bdc_readl(bdc->regs, BDC_BDCSC);
 107         /* if BDC is already in running state then do not do anything */
 108         if (BDC_CSTS(temp) == BDC_NOR) {
 109                 dev_warn(bdc->dev, "bdc is already in running state\n");
 110                 return 0;
 111         }
 112         temp &= ~BDC_COP_MASK;
 113         temp |= BDC_COP_RUN;
 114         temp |= BDC_COS;
 115         bdc_writel(bdc->regs, BDC_BDCSC, temp);
 116         ret = poll_oip(bdc, BDC_COP_TIMEOUT);
 117         if (ret) {
 118                 dev_err(bdc->dev, "bdc run operation failed:%d", ret);
 119                 return ret;
 120         }
 121         temp = bdc_readl(bdc->regs, BDC_BDCSC);
 122         if (BDC_CSTS(temp) != BDC_NOR) {
 123                 dev_err(bdc->dev, "bdc not in normal mode after RUN op :%d\n",
 124                                                                 BDC_CSTS(temp));
 125                 return -ESHUTDOWN;
 126         }
 127
 128         return 0;
 129 }
 130
 131 /*
 132  * Present the termination to the host, typically called from upstream port
 133  * event with Vbus present =1
 134  */
 135 void bdc_softconn(struct bdc *bdc)
 136 {
 137         u32 uspc;
 138
 139         uspc = bdc_readl(bdc->regs, BDC_USPC);
 140         uspc &= ~BDC_PST_MASK;
 141         uspc |= BDC_LINK_STATE_RX_DET;
 142         uspc |= BDC_SWS;
 143         dev_dbg(bdc->dev, "%s () uspc=%08x\n", __func__, uspc);
 144         bdc_writel(bdc->regs, BDC_USPC, uspc);
 145 }
 146
 147 /* Remove the termination */
 148 void bdc_softdisconn(struct bdc *bdc)
 149 {
 150         u32 uspc;
 151
 152         uspc = bdc_readl(bdc->regs, BDC_USPC);
 153         uspc |= BDC_SDC;
 154         uspc &= ~BDC_SCN;
 155         dev_dbg(bdc->dev, "%s () uspc=%x\n", __func__, uspc);
 156         bdc_writel(bdc->regs, BDC_USPC, uspc);
 157 }
 158
 159 /* Set up the scratchpad buffer array and scratchpad buffers, if needed. */
 160 static int scratchpad_setup(struct bdc *bdc)
 161 {
 162         int sp_buff_size;
 163         u32 low32;
 164         u32 upp32;
 165
 166         sp_buff_size = BDC_SPB(bdc_readl(bdc->regs, BDC_BDCCFG0));
 167         dev_dbg(bdc->dev, "%s() sp_buff_size=%d\n", __func__, sp_buff_size);
 168         if (!sp_buff_size) {
 169                 dev_dbg(bdc->dev, "Scratchpad buffer not needed\n");
 170                 return 0;
 171         }
 172         /* Refer to BDC spec, Table 4 for description of SPB */
 173         sp_buff_size = 1 << (sp_buff_size + 5);
 174         dev_dbg(bdc->dev, "Allocating %d bytes for scratchpad\n", sp_buff_size);
 175         bdc->scratchpad.buff  =  dma_alloc_coherent(bdc->dev, sp_buff_size,
 176                                                     &bdc->scratchpad.sp_dma,
 177                                                     GFP_KERNEL);
 178
 179         if (!bdc->scratchpad.buff)
 180                 goto fail;
 181
 182         bdc->sp_buff_size = sp_buff_size;
 183         bdc->scratchpad.size = sp_buff_size;
 184         low32 = lower_32_bits(bdc->scratchpad.sp_dma);
 185         upp32 = upper_32_bits(bdc->scratchpad.sp_dma);
 186         cpu_to_le32s(&low32);
 187         cpu_to_le32s(&upp32);
 188         bdc_writel(bdc->regs, BDC_SPBBAL, low32);
 189         bdc_writel(bdc->regs, BDC_SPBBAH, upp32);
 190         return 0;
 191
 192 fail:
 193         bdc->scratchpad.buff = NULL;
 194
 195         return -ENOMEM;
 196 }
 197
 198 /* Allocate the status report ring */
 199 static int setup_srr(struct bdc *bdc, int interrupter)
 200 {
 201         dev_dbg(bdc->dev, "%s() NUM_SR_ENTRIES:%d\n", __func__, NUM_SR_ENTRIES);
 202         /* Reset the SRR */
 203         bdc_writel(bdc->regs, BDC_SRRINT(0), BDC_SRR_RWS | BDC_SRR_RST);
 204         bdc->srr.dqp_index = 0;
 205         /* allocate the status report descriptors */
 206         bdc->srr.sr_bds = dma_alloc_coherent(bdc->dev,
 207                                              NUM_SR_ENTRIES * sizeof(struct bdc_bd),
 208                                              &bdc->srr.dma_addr, GFP_KERNEL);
 209         if (!bdc->srr.sr_bds)
 210                 return -ENOMEM;
 211
 212         return 0;
 213 }
 214
 215 /* Initialize the HW regs and internal data structures */
 216 static void bdc_mem_init(struct bdc *bdc, bool reinit)
 217 {
 218         u8 size = 0;
 219         u32 usb2_pm;
 220         u32 low32;
 221         u32 upp32;
 222         u32 temp;
 223
 224         dev_dbg(bdc->dev, "%s ()\n", __func__);
 225         bdc->ep0_state = WAIT_FOR_SETUP;
 226         bdc->dev_addr = 0;
 227         bdc->srr.eqp_index = 0;
 228         bdc->srr.dqp_index = 0;
 229         bdc->zlp_needed = false;
 230         bdc->delayed_status = false;
 231
 232         bdc_writel(bdc->regs, BDC_SPBBAL, bdc->scratchpad.sp_dma);
 233         /* Init the SRR */
 234         temp = BDC_SRR_RWS | BDC_SRR_RST;
 235         /* Reset the SRR */
 236         bdc_writel(bdc->regs, BDC_SRRINT(0), temp);
 237         dev_dbg(bdc->dev, "bdc->srr.sr_bds =%p\n", bdc->srr.sr_bds);
 238         temp = lower_32_bits(bdc->srr.dma_addr);
 239         size = fls(NUM_SR_ENTRIES) - 2;
 240         temp |= size;
 241         dev_dbg(bdc->dev, "SRRBAL[0]=%08x NUM_SR_ENTRIES:%d size:%d\n",
 242                                                 temp, NUM_SR_ENTRIES, size);
 243
 244         low32 = lower_32_bits(temp);
 245         upp32 = upper_32_bits(bdc->srr.dma_addr);
 246         cpu_to_le32s(&low32);
 247         cpu_to_le32s(&upp32);
 248
 249         /* Write the dma addresses into regs*/
 250         bdc_writel(bdc->regs, BDC_SRRBAL(0), low32);
 251         bdc_writel(bdc->regs, BDC_SRRBAH(0), upp32);
 252
 253         temp = bdc_readl(bdc->regs, BDC_SRRINT(0));
 254         temp |= BDC_SRR_IE;
 255         temp &= ~(BDC_SRR_RST | BDC_SRR_RWS);
 256         bdc_writel(bdc->regs, BDC_SRRINT(0), temp);
 257
 258         /* Set the Interrupt Coalescence ~500 usec */
 259         temp = bdc_readl(bdc->regs, BDC_INTCTLS(0));
 260         temp &= ~0xffff;
 261         temp |= INT_CLS;
 262         bdc_writel(bdc->regs, BDC_INTCTLS(0), temp);
 263
 264         usb2_pm = bdc_readl(bdc->regs, BDC_USPPM2);
 265         dev_dbg(bdc->dev, "usb2_pm=%08x", usb2_pm);
 266         /* Enable hardware LPM Enable */
 267         usb2_pm |= BDC_HLE;
 268         bdc_writel(bdc->regs, BDC_USPPM2, usb2_pm);
 269
 270         /* readback for debug */
 271         usb2_pm = bdc_readl(bdc->regs, BDC_USPPM2);
 272         dev_dbg(bdc->dev, "usb2_pm=%08x\n", usb2_pm);
 273
 274         /* Disable any unwanted SR's on SRR */
 275         temp = bdc_readl(bdc->regs, BDC_BDCSC);
 276         /* We don't want Microframe counter wrap SR */
 277         temp |= BDC_MASK_MCW;
 278         bdc_writel(bdc->regs, BDC_BDCSC, temp);
 279
 280         /*
 281          * In some error cases, driver has to reset the entire BDC controller
 282          * in that case reinit is passed as 1
 283          */
 284         if (reinit) {
 285                 /* Enable interrupts */
 286                 temp = bdc_readl(bdc->regs, BDC_BDCSC);
 287                 temp |= BDC_GIE;
 288                 bdc_writel(bdc->regs, BDC_BDCSC, temp);
 289                 /* Init scratchpad to 0 */
 290                 memset(bdc->scratchpad.buff, 0, bdc->sp_buff_size);
 291                 /* Initialize SRR to 0 */
 292                 memset(bdc->srr.sr_bds, 0,
 293                                         NUM_SR_ENTRIES * sizeof(struct bdc_bd));
 294         } else {
 295                 /* One time initiaization only */
 296                 /* Enable status report function pointers */
 297                 bdc->sr_handler[0] = bdc_sr_xsf;
 298                 bdc->sr_handler[1] = bdc_sr_uspc;
 299
 300                 /* EP0 status report function pointers */
 301                 bdc->sr_xsf_ep0[0] = bdc_xsf_ep0_setup_recv;
 302                 bdc->sr_xsf_ep0[1] = bdc_xsf_ep0_data_start;
 303                 bdc->sr_xsf_ep0[2] = bdc_xsf_ep0_status_start;
 304         }
 305 }
 306
 307 /* Free the dynamic memory */
 308 static void bdc_mem_free(struct bdc *bdc)
 309 {
 310         dev_dbg(bdc->dev, "%s\n", __func__);
 311         /* Free SRR */
 312         if (bdc->srr.sr_bds)
 313                 dma_free_coherent(bdc->dev,
 314                                         NUM_SR_ENTRIES * sizeof(struct bdc_bd),
 315                                         bdc->srr.sr_bds, bdc->srr.dma_addr);
 316
 317         /* Free scratchpad */
 318         if (bdc->scratchpad.buff)
 319                 dma_free_coherent(bdc->dev, bdc->sp_buff_size,
 320                                 bdc->scratchpad.buff, bdc->scratchpad.sp_dma);
 321
 322         /* Destroy the dma pools */
 323         dma_pool_destroy(bdc->bd_table_pool);
 324
 325         /* Free the bdc_ep array */
 326         kfree(bdc->bdc_ep_array);
 327
 328         bdc->srr.sr_bds = NULL;
 329         bdc->scratchpad.buff = NULL;
 330         bdc->bd_table_pool = NULL;
 331         bdc->bdc_ep_array = NULL;
 332 }
 333
 334 /*
 335  * bdc reinit gives a controller reset and reinitialize the registers,
 336  * called from disconnect/bus reset scenario's, to ensure proper HW cleanup
 337  */
 338 int bdc_reinit(struct bdc *bdc)
 339 {
 340         int ret;
 341
 342         dev_dbg(bdc->dev, "%s\n", __func__);
 343         ret = bdc_stop(bdc);
 344         if (ret)
 345                 goto out;
 346
 347         ret = bdc_reset(bdc);
 348         if (ret)
 349                 goto out;
 350
 351         /* the reinit flag is 1 */
 352         bdc_mem_init(bdc, true);
 353         ret = bdc_run(bdc);
 354 out:
 355         bdc->reinit = false;
 356
 357         return ret;
 358 }
 359
 360 /* Allocate all the dyanmic memory */
 361 static int bdc_mem_alloc(struct bdc *bdc)
 362 {
 363         u32 page_size;
 364         unsigned int num_ieps, num_oeps;
 365
 366         dev_dbg(bdc->dev,
 367                 "%s() NUM_BDS_PER_TABLE:%d\n", __func__,
 368                 NUM_BDS_PER_TABLE);
 369         page_size = BDC_PGS(bdc_readl(bdc->regs, BDC_BDCCFG0));
 370         /* page size is 2^pgs KB */
 371         page_size = 1 << page_size;
 372         /* KB */
 373         page_size <<= 10;
 374         dev_dbg(bdc->dev, "page_size=%d\n", page_size);
 375
 376         /* Create a pool of bd tables */
 377         bdc->bd_table_pool =
 378             dma_pool_create("BDC BD tables", bdc->dev, NUM_BDS_PER_TABLE * 16,
 379                                                                 16, page_size);
 380
 381         if (!bdc->bd_table_pool)
 382                 goto fail;
 383
 384         if (scratchpad_setup(bdc))
 385                 goto fail;
 386
 387         /* read from regs */
 388         num_ieps = NUM_NCS(bdc_readl(bdc->regs, BDC_FSCNIC));
 389         num_oeps = NUM_NCS(bdc_readl(bdc->regs, BDC_FSCNOC));
 390         /* +2: 1 for ep0 and the other is rsvd i.e. bdc_ep[0] is rsvd */
 391         bdc->num_eps = num_ieps + num_oeps + 2;
 392         dev_dbg(bdc->dev,
 393                 "ieps:%d eops:%d num_eps:%d\n",
 394                 num_ieps, num_oeps, bdc->num_eps);
 395         /* allocate array of ep pointers */
 396         bdc->bdc_ep_array = kcalloc(bdc->num_eps, sizeof(struct bdc_ep *),
 397                                                                 GFP_KERNEL);
 398         if (!bdc->bdc_ep_array)
 399                 goto fail;
 400
 401         dev_dbg(bdc->dev, "Allocating sr report0\n");
 402         if (setup_srr(bdc, 0))
 403                 goto fail;
 404
 405         return 0;
 406 fail:
 407         dev_warn(bdc->dev, "Couldn't initialize memory\n");
 408         bdc_mem_free(bdc);
 409
 410         return -ENOMEM;
 411 }
 412
 413 /* opposite to bdc_hw_init */
 414 static void bdc_hw_exit(struct bdc *bdc)
 415 {
 416         dev_dbg(bdc->dev, "%s ()\n", __func__);
 417         bdc_mem_free(bdc);
 418 }
 419
 420 /* Initialize the bdc HW and memory */
 421 static int bdc_hw_init(struct bdc *bdc)
 422 {
 423         int ret;
 424
 425         dev_dbg(bdc->dev, "%s ()\n", __func__);
 426         ret = bdc_reset(bdc);
 427         if (ret) {
 428                 dev_err(bdc->dev, "err resetting bdc abort bdc init%d\n", ret);
 429                 return ret;
 430         }
 431         ret = bdc_mem_alloc(bdc);
 432         if (ret) {
 433                 dev_err(bdc->dev, "Mem alloc failed, aborting\n");
 434                 return -ENOMEM;
 435         }
 436         bdc_mem_init(bdc, 0);
 437         bdc_dbg_regs(bdc);
 438         dev_dbg(bdc->dev, "HW Init done\n");
 439
 440         return 0;
 441 }
 442
 443 static int bdc_phy_init(struct bdc *bdc)
 444 {
 445         int phy_num;
 446         int ret;
 447
 448         for (phy_num = 0; phy_num < bdc->num_phys; phy_num++) {
 449                 ret = phy_init(bdc->phys[phy_num]);
 450                 if (ret)
 451                         goto err_exit_phy;
 452                 ret = phy_power_on(bdc->phys[phy_num]);
 453                 if (ret) {
 454                         phy_exit(bdc->phys[phy_num]);
 455                         goto err_exit_phy;
 456                 }
 457         }
 458
 459         return 0;
 460
 461 err_exit_phy:
 462         while (--phy_num >= 0) {
 463                 phy_power_off(bdc->phys[phy_num]);
 464                 phy_exit(bdc->phys[phy_num]);
 465         }
 466
 467         return ret;
 468 }
 469
 470 static void bdc_phy_exit(struct bdc *bdc)
 471 {
 472         int phy_num;
 473
 474         for (phy_num = 0; phy_num < bdc->num_phys; phy_num++) {
 475                 phy_power_off(bdc->phys[phy_num]);
 476                 phy_exit(bdc->phys[phy_num]);
 477         }
 478 }
 479
 480 static int bdc_probe(struct platform_device *pdev)
 481 {
 482         struct bdc *bdc;
 483         struct resource *res;
 484         int ret = -ENOMEM;
 485         int irq;
 486         u32 temp;
 487         struct device *dev = &pdev->dev;
 488         struct clk *clk;
 489         int phy_num;
 490
 491         dev_dbg(dev, "%s()\n", __func__);
 492
 493         clk = devm_clk_get(dev, "sw_usbd");
 494         if (IS_ERR(clk)) {
 495                 dev_info(dev, "Clock not found in Device Tree\n");
 496                 clk = NULL;
 497         }
 498
 499         ret = clk_prepare_enable(clk);
 500         if (ret) {
 501                 dev_err(dev, "could not enable clock\n");
 502                 return ret;
 503         }
 504
 505         bdc = devm_kzalloc(dev, sizeof(*bdc), GFP_KERNEL);
 506         if (!bdc)
 507                 return -ENOMEM;
 508
 509         bdc->clk = clk;
 510
 511         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 512         bdc->regs = devm_ioremap_resource(dev, res);
 513         if (IS_ERR(bdc->regs)) {
 514                 dev_err(dev, "ioremap error\n");
 515                 return -ENOMEM;
 516         }
 517         irq = platform_get_irq(pdev, 0);
 518         if (irq < 0) {
 519                 dev_err(dev, "platform_get_irq failed:%d\n", irq);
 520                 return irq;
 521         }
 522         spin_lock_init(&bdc->lock);
 523         platform_set_drvdata(pdev, bdc);
 524         bdc->irq = irq;
 525         bdc->dev = dev;
 526         dev_dbg(dev, "bdc->regs: %p irq=%d\n", bdc->regs, bdc->irq);
 527
 528         bdc->num_phys = of_count_phandle_with_args(dev->of_node,
 529                                                 "phys", "#phy-cells");
 530         if (bdc->num_phys > 0) {
 531                 bdc->phys = devm_kcalloc(dev, bdc->num_phys,
 532                                         sizeof(struct phy *), GFP_KERNEL);
 533                 if (!bdc->phys)
 534                         return -ENOMEM;
 535         } else {
 536                 bdc->num_phys = 0;
 537         }
 538         dev_info(dev, "Using %d phy(s)\n", bdc->num_phys);
 539
 540         for (phy_num = 0; phy_num < bdc->num_phys; phy_num++) {
 541                 bdc->phys[phy_num] = devm_of_phy_get_by_index(
 542                         dev, dev->of_node, phy_num);
 543                 if (IS_ERR(bdc->phys[phy_num])) {
 544                         ret = PTR_ERR(bdc->phys[phy_num]);
 545                         dev_err(bdc->dev,
 546                                 "BDC phy specified but not found:%d\n", ret);
 547                         return ret;
 548                 }
 549         }
 550
 551         ret = bdc_phy_init(bdc);
 552         if (ret) {
 553                 dev_err(bdc->dev, "BDC phy init failure:%d\n", ret);
 554                 return ret;
 555         }
 556
 557         temp = bdc_readl(bdc->regs, BDC_BDCCAP1);
 558         if ((temp & BDC_P64) &&
 559                         !dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64))) {
 560                 dev_dbg(dev, "Using 64-bit address\n");
 561         } else {
 562                 ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
 563                 if (ret) {
 564                         dev_err(dev,
 565                                 "No suitable DMA config available, abort\n");
 566                         return -ENOTSUPP;
 567                 }
 568                 dev_dbg(dev, "Using 32-bit address\n");
 569         }
 570         ret = bdc_hw_init(bdc);
 571         if (ret) {
 572                 dev_err(dev, "BDC init failure:%d\n", ret);
 573                 goto phycleanup;
 574         }
 575         ret = bdc_udc_init(bdc);
 576         if (ret) {
 577                 dev_err(dev, "BDC Gadget init failure:%d\n", ret);
 578                 goto cleanup;
 579         }
 580         return 0;
 581
 582 cleanup:
 583         bdc_hw_exit(bdc);
 584 phycleanup:
 585         bdc_phy_exit(bdc);
 586         return ret;
 587 }
 588
 589 static int bdc_remove(struct platform_device *pdev)
 590 {
 591         struct bdc *bdc;
 592
 593         bdc  = platform_get_drvdata(pdev);
 594         dev_dbg(bdc->dev, "%s ()\n", __func__);
 595         bdc_udc_exit(bdc);
 596         bdc_hw_exit(bdc);
 597         bdc_phy_exit(bdc);
 598         clk_disable_unprepare(bdc->clk);
 599         return 0;
 600 }
 601
 602 #ifdef CONFIG_PM_SLEEP
 603 static int bdc_suspend(struct device *dev)
 604 {
 605         struct bdc *bdc = dev_get_drvdata(dev);
 606
 607         clk_disable_unprepare(bdc->clk);
 608         return 0;
 609 }
 610
 611 static int bdc_resume(struct device *dev)
 612 {
 613         struct bdc *bdc = dev_get_drvdata(dev);
 614         int ret;
 615
 616         ret = clk_prepare_enable(bdc->clk);
 617         if (ret) {
 618                 dev_err(bdc->dev, "err enabling the clock\n");
 619                 return ret;
 620         }
 621         ret = bdc_reinit(bdc);
 622         if (ret) {
 623                 dev_err(bdc->dev, "err in bdc reinit\n");
 624                 return ret;
 625         }
 626
 627         return 0;
 628 }
 629
 630 #endif /* CONFIG_PM_SLEEP */
 631
 632 static SIMPLE_DEV_PM_OPS(bdc_pm_ops, bdc_suspend,
 633                 bdc_resume);
 634
 635 static const struct of_device_id bdc_of_match[] = {
 636         { .compatible = "brcm,bdc-v0.16" },
 637         { .compatible = "brcm,bdc" },
 638         { /* sentinel */ }
 639 };
 640
 641 static struct platform_driver bdc_driver = {
 642         .driver         = {
 643                 .name   = BRCM_BDC_NAME,
 644                 .pm = &bdc_pm_ops,
 645                 .of_match_table = bdc_of_match,
 646         },
 647         .probe          = bdc_probe,
 648         .remove         = bdc_remove,
 649 };
 650
 651 module_platform_driver(bdc_driver);
 652 MODULE_AUTHOR("Ashwini Pahuja <ashwini.linux@gmail.com>");
 653 MODULE_LICENSE("GPL");
 654 MODULE_DESCRIPTION(BRCM_BDC_DESC);